1. Field of the Invention
The present invention relates generally to a photo conductor drum cartridge, and more specifically to a driving unit for a photo conductor drum cartridge that is reusable and provides a convenient detachment of a photo conductor drum from a shaft.
2. Description of the Related Art
FIGS. 1 and 2 show a conventional photo conductor drum cartridge 1 for use in a photocopier, comprising a housing 2, a shaft 3 mounted in the housing 2 and provided with an annual groove 91 at each of two opposite ends thereof for engagement with a C-shaped fastener 92 such that the shaft 3 can be rotatably mounted to the housing 2, a photo conductor drum 4 sleeved on the shaft 3, a support wheel 5 sleeved on the right end of the shaft 3 and engaged with the right end of the photo conductor drum 4, a driving wheel 6 sleeved on the left end of the shaft 3 and engaged with the left end of the photo conductor drum 4, a conducting plate 7 mounted on the driving wheel 6 in such a way that the outer periphery of the conducting plate 7 is abutted against the inner periphery of the photo conductor drum 4 and provided with a axial hole 8 for penetration of the shaft 3, and an elastic arm 9 extending from the periphery of the axial hole 8 and stopped against the shaft 3. Therefore, the inner periphery of the photo-conductor drum 4 can be electrically grounded through the conductor plate 7 and the shaft 3.
When the photo conductor drum cartridge 1 is assembled, the driving wheel 6 and the photo conductor drum 4 are engaged with each other firstly, and then the shaft 3 is inserted through the driving wheel 6 and the axial hole 8 of the conducting plate 7, as shown in FIGS. 3 and 4. When the shaft 3 is moved rightwards relative to the photo conductor drum 4, the shaft 3 will push the elastic arm 9 of the conducting plate 7 away to cause an elastic deformation of the elastic arm 9 such that the distal end of the elastic arm 9 can run over the annual groove 91 and then keep contacted with the shaft 3.
When the photo conductor drum 4 is malfunction and then needs to be repaired or replaced, a maintenance worker has to dismount the shaft 3 from the photo conductor drum 4. As shown in FIG. 5, when the shaft 3 is pulled leftwards relative to the photo conductor drum 4, the distal end of the elastic arm 9 may be jammed in the groove 91 to cause the distortion of the elastic arm 9. Under this circumstance, it can be seen that the shaft 3 will be difficultly drawn out from the driving wheel 6, and the conducting plate 7 will be easily damaged and then can not be reused.